Power-transmitting device



(No Model.)

J. WALKER.

POWER TRANSMITTING DEVICE.

No. 469,491. Patented Feb. 23, 1892.

WWW

m: "cams PETERS cm, moro-umm, WASNINGTD UNITED STATES PATENT OFFICE.

JOHN WALKER, OF CLEVELAND, OHIO.

POWER-TRANSMITTING DEVICE.

SPECIFICATION forming part of Letters Patent No. 469,491, dated February 23, 1892.

- Application filed June 28,1390- Serial No. 357,046- (No model.)

To all whom it may concern.-

Be it known that I, JOHN WALKER, of the city of Cleveland, in the county of Cuyahoga and State of Ohio, have invented certainlmprovements in Power-Transmitting Devices, of which the following is a specification.

This invention relates to certain improvements in that class of power-transmitting mechanism in which a series of independent endless ropes are employed to convey rotary motion from one drum to another. Such ropes are made of cotton, and the whole arrangement is technically known as the cottonrope drive. It was originally devised as a substitute for the belt in cotton-mills, as the vibration of the belt was found to interfere with the uniformity in texture of the cloth produced. The cotton-rope drive is now used in cable railways to transmit motion from a grooved driver to a similarly-grooved driven drum and in place of toothed gearing. The ropes are made slack to increase their traction. Before mypresent invention the grooves were formed in the drums proper or in parts thereof which move in unison with the shafts to which the drums are secured. Now were it possible to make the cotton ropes of absolutely the same diameter throughouttheirlength and of the same weight per foot and of the same degree of hardness, so that they would pass to exactly the same depth within the grooves,

and also to splice the whole series of ropes, so that their lengths would be precisely equal, all the ropes would havea common tension and the whole driving strain would be accurately and equally distributed among them; but such mechanical perfection cannot be attained, and in the practical operation of the rope drive some of the ropes perform nearly all the labor, the others being to a great extent inoperative as power-transmitting devices; and as it is impossible to ascertain what proportion of the whole labor is borne by each rope the only means of securing absolute safety has been to use in each drive a much greater number of ropes than were theoretically required. WVith my invention, as hereinafter described, a uniform strain is applied to all the independent ropes, and in view of this their number may be reduced without incurring any danger of breakage.

In the further description of the said invention which follows reference is made to the accompanying drawings, forming a part hereof, and in which- Figure 1 is a side elevation of a driver and a driven drum connected by a series of independent endless ropes in accordance with my invention. Fig. 2 is a top or plan view of the same with some of the ropes removed to show the drums. Fig. 3 is an enlarged cross-section of two rings and a part of the drum proper, together with two ropes.

Similar letters of reference indicate similar parts in all the figures.

In the said drawings, A represents the drums proper, and B independentrings adapted to turn loosely and independently of each other on the smooth circumference of the drums. These rings are grooved, as shown in the drawings-that is to say, the grooves are reduced at the bottom to a width considerably less than the diameter of the independent endless ropes, which are denoted by C. By this means the comparatively soft ropes are forced tightly into the grooves and their traction increased. As the strain on the ropes is equalized by the independent oircumferen tial adjustment of the grooved rings on the drums proper, a uniform length of rope in the series is not essential, and the work of cutting and splicing the ropes is therefore much sim' plified. g

In Fig. 1 the ropes are illustrated as of different lengths, which is always the case even when a common length is aimed at.

I claim as my invention- The within-described improvement in rope drives, consisting of a pair of drums, each having a series of peripheral grooved rings adapted to turn independently of each other and of its drum, combined with independent endless ropes rove around said drums, each of said ropes resting in the grooves of oppositelyplaced rings of the drums, whereby a uniform strain is applied to said ropes, substantially as set forth.

JOHN \VALKER.

lVitnesses:

J. J. BEVER, S. A. WACKER AN. 

